2 Chicks died within 24 hrs - thought?

My bobwhites are just over a week old. All have seemed healthy but all of a sudden, I've had 2 deaths in the last 24 hours.
My broader is a 20 gallon long aquarium and I've recently started using pine shavings that I bought at Tractor Supply. Do you think that the pine shavings can be the problem? An aquarium in pretty unventilated so thats the only thing I can think of.
I have a cage outside that I'm thinking of moving them to. There will be more ventilation so maybe that will help. Also it's larger - they need more room as they're growing fast!
Has anyone else had this experience? Do you think I'm on the right track in thinking that it may be a ventilation / respiratory issue?

Death of chicks is generally caused by a heat and or draft issue. Either it is too hot, too cold, or there are drafts.

Use a reliable thermometer, placed directly beneath the lamp on the floor. Bobs are started at 97 degrees and lowered by 5 degrees each week for 5 or 6 weeks. Water and food are placed on the other side of the brooder so that they have to leave the direct heat to get to the goods. The brooder lamp on the other side so that there are cool spots along the edges and other side of the brooder to cool off.

The brooder should not be so big that there are drafts, nor too small that there are no cool spots in the brooder. Do not cover the lid of the brooder with anything but a screen or wire for good heat and oxygen exchange.

If the chicks are piling up on each other under the light, they are too cold. If they are laid out along the edges, wings out, they are over heating.

Another thing that kills babies is the food is not crushed small enough to eat, or they do not know where it is. Always lay down paper towels the first week and sprinkle crushed food around the brooder floor near the feeder, so they know where the food is stored. Always dip everybody's beak in the water the day of hatch.

Thank you TwoCrows. I believe all of those conditions are being met. They're just over a week old. I double checked the temperature with a second thermometer and its at about 94 under the heat source. I crush their Gamebird Starter feed with a smoothie maker. There's a wire lid on the aquarium. There could possibly be some air going in that direction from an a/c vent. Ill turn that and see if that makes a difference.

Yes, any moving cool air near the brooder could be sucking the heat out and creating a draft. Quail babies are highly suseptable to dying in drafts. See shutting off that AC vent helps with curbing the deaths.

I turned the vent and also put up a piece of cardboard to block any air that might be blowing in - and woke up to find another dead chick. I'm going to relocate the cage to the sunroom today to see if that helps. I just don't know what else to try.

Have you hatched anything else in this incubator lately? It is possible they have some sort of bacterial infection from an unclean incubator. Where did you get the eggs? Sometimes chicks hatch with virus's or bacterial infections that can kill them. Genetic in origin coming from the parent birds. You could try some antibiotics in the water for 7 days and see if that doesn't clear it up.

It's my first batch ever. I ordered the Hovabator from the manufacturer and it came with 30 bob white eggs.
Where does one get antibiotics for quail? Pet store?
I've moved them to a bigger brooder in a different location.

If you have a feed store near by, you can usually get Duramycin there. Or you can order it on line. Duramycin is an good broad spectrum antibiotic and takes care of many strains of bacteria. I hope you can get this resolved soon.

Thank you so much for your responses. I've lost 6 so far. Today I changed out their pine shavings for a brand that specifies kiln dried pine shavings.
I'll go to Tractor Supply tomorrow and see what they have.

Ok I changed to kiln dried pine shavings yesterday afternoon. I woke up this morning and found one dead chick. I was at Tractor Supply first thing this morning and got some Duramycin and promptly added a dose to their water. I've had a good day - no deaths so far so I'm encouraged. Wish us luck through the night!